Caring for your prints, drawings and watercolours

Works of art on paper appear in almost every private or public collection and cover a vast range, both in subject matter and value.

In Europe, paper has been in common use as a picture support since the mid-fifteenth century and is still the material on which the majority of artists’ images are produced. The materials From old master drawings to contemporary prints, the paper is fundamentally made of cellulose in the form of finely broken down plant fibres. In its purest form, cellulose is extremely durable, but additions can cause deterioration, usually through acid degradation, which weakens the fibres. The media used on the paper may be unstable too: pigments can fade or darken, some drawing inks bleed or corrode the paper, pastels and charcoal get smudged, thick paint like oils and gouache can flake.

Causes of damage Any exposure to light harms media and paper, but poor quality mounting and framing damages more works of art on paper than any other agent. Prints, drawings and watercolours can be ruined through contact with unsuitable framing materials, just as they can by amateur restoration and the use of inappropriate techniques in handling, storage and display. Atmospheric pollutants, for example sulphur and particulates, are implicated in the destruction of paper and they can change artists’ colours too. Biological agents, like insects and mould, affect paper, but they will only flourish as a result of uncontrolled environmental factors, such as high humidity and temperature.

Signs of damage Most owners of old watercolours, drawings and prints are familiar with the disfiguring brown spots called ‘foxing’. The stains are caused by bacteria or mould which generally grows on acidic paper when the humidity is high, or when metallic particles from the paper making process become embedded in the fibres.

Watercolour by JMW Turner showing fading of pigments where exposed to light

Paper will turn brown and brittle when cardboard containing unpurified wood pulp is pressed against it and that is how so many framed works of art on paper are damaged. They are stained on the back and have a brown or orange line around the edge of the image where the acidic overmount has ‘burnt’ the paper. Yellow stains on paper, especially in regular patches, can be due to glue or adhesive tapes used to fix the picture into a mount. Self-adhesive tapes are particularly damaging because the adhesive creeps into the paper and becomes impossible to remove. Too much light is usually to blame when you see a watercolour painting with a strange colour balance, or an ink drawing, which has lost its detail. The original colouring can often be found under the mount.

A certain amount of cockling or undulation is usual in handmade paper, but if the work of art is badly distorted, bowing towards the glass in a frame and perhaps wrinkled or even torn at the corners, then it is probably stuck down around the edges. Paper moves naturally in response to changes in humidity and it is better not to restrain it.

What you can do Storage and display The best way to keep most prints, drawings and watercolours is in a specially designed case called a Solander box. The works of art are mounted in conservation quality materials, must rest horizontally in drawers or on shelves. When handling the work of art, you should touch the paper as little as possible and keep your fingers away from the image. Pastel and charcoal drawings need extra care because the image may offset or smudge with the slightest pressure, so you could consider keeping them permanently framed within a mount that has been rebated to prevent any static or friction. Contemporary prints should not be handled directly either, because their immaculate paper is easily marked with skin oil and moisture. Keep them in a mount or acid-free paper folder. Attaching is a good barrier material from atmospheric pollutants or fluctuations in RH.

Protect framed prints, drawings and watercolours from daylight. Particularly avoid south facing light and try not to hang them directly against the interior of the outside wall of a building; the comparatively low temperature can cause condensation and mould growth inside. Conversely, a radiator or spotlight will dry the air out, and incidentally concentrate dust by convection currents. When choosing a suitable storage area, avoid damp cellars and un-insulated attics.

If prints and drawings get really wet, for example from a burst pipe, it is better to lay them out separately on blotting paper to dry with good air circulation, rather than to use an artificial heat source. In the case of a serious flood or a fire, get help from a conservator as soon as possible.

Mounting and framing If you have been to a picture framer recently, you may already know that many now offer mounting and framing to ‘conservation standards’. But you also need to know that these standards are not yet universally agreed or applied. You will still have to specify exactly what you want to safeguard your works of art. Ask the framer to follow the advice in the Institute of Paper Conservation leaflet, Guidelines for Conservation Framing, and explain that you are looking for positive answers to these five questions. Use UV protected glass.

• Will both the front and the back of the mount be made of solid core 100% cotton board (known as ‘museum board’), which is the best quality, or purified wood pulp board (known as ‘conservation board’)? • If there is no window or overmount, will the glazing material be spaced away from the picture surface? • Will the work of art be attached to the backmount only with acid-free paper hinges and a water-soluble adhesive? • Will there be an isolating layer between the backmount and a potentially damaging but necessary frame backboard, made of plywood or hardboard for example? • Will the frame itself have enough depth in the rebate to accommodate the mount, the isolating layer and the backboard and strength to take hanging fittings secured to the frame and not the backboard?

If you are not confident that the framer can meet these standards, ask a paper conservator to help you find one who can.

What you can’t do When it is too late for preventive conservation and the damage is already done, there is little that you as a collector can do to conserve and restore works of art on paper. Traditional remedies such as bread crumbs or bread to clean off dirt and commercially produced tapes to repair tears will do more harm than good.

Contact a paper conservator through the Institute of Paper Conservation and they will advise on the most appropriate treatment for your picture. With professional treatment, the condition of the paper and image can be stabilised so that their deterioration will not progress. Although faded colours cannot be restored to their original brightness and severe paper staining may only be reduced, most damage can be corrected by a skilled conservator.

Finding a conservator IPC operates a professional accreditation scheme to protect the users of conservation services, whether individuals or large public institutions. The scheme is run in partnership with other conservation bodies. Accredited members are designated as ACR MIPC.

IPC supplies free of charge, the names and addresses of ACRs either by geographical area or particular expertise. This service is open to both individuals and institutions, for a single item or collections. ACRs may also give advice on preventive conservation, disaster planning, storage and display.

The Institute of Paper Conservation is the leading organisation devoted solely to the conservation and care of paper, books and related materials. The Institute of Paper Conservation is a mail: information@ipc.org.uk website: www.ipc.org.uk

The recommendations in this leaflet are intended as guidance only. IPC does not assume responsibility or liability.